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 #35096 - 06/22/10 04:41 AM Re: Orion, Mission to Alpha Centauri kallog Megastar Registered: 03/17/10 Posts: 1100 Where did 15,600 kg m/s come from?That's the change in momentum of the mass as it goes through the 1st turnaround (for the 2nd time).Speed on entering turnaround = -39m/s + -39m/s = -78m/sMomentum entering turnaround = -78m/s * 100kg = -7800 kg m/sMomentum exiting turnaround = 78m/s * 100kg = 7800 kgm/sChange in momentum of mass through turnaround = 7800 - -7800 = 15,600 kg m/sChange in momentum of pipe as mass turns around= -15,600 kg m/s Edited by kallog (06/22/10 04:46 AM) Top
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 #35098 - 06/22/10 11:42 AM Re: Orion, Mission to Alpha Centauri paul Megastar Registered: 03/21/06 Posts: 4136 Quote: This means the -3900N force was applied for 2 seconds. NO !!!! the mass has a final velocity of 39.038 m/s when it enters the turnaround after being accelerated.the turnaround would have to have a lenght of 39.038 meters * 2 = 78.076 metersfor the mass to consume 2 entire seconds while passing through it.so your wrong.Quote:It's meaningless to add up forces while ignoring the times they're applied for. I'll include time below... and its even less meaningless to include erroneous times , Im not sure why your so concerned with time as the time is given in the acceleration of the mass.ie...5 meters / SECOND / SECOND...meaning each second..Quote:Maybe it's travelling a longer and longer distance each cycle too, or maybe it isn't. Havn't worked that out. maybe that is where your insertion of 2 seconds will come in !!!LOL. _________________________ 3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science. Top
 #35100 - 06/22/10 12:57 PM Re: Orion, Mission to Alpha Centauri [Re: paul] kallog Megastar Registered: 03/17/10 Posts: 1100 Originally Posted By: paulNO !!!! Yes. It's your design. You specified 3900N. That requires 2s, and 78m. If you want a shorter turnaround then you need to choose a higher force to get the job done faster. The value of this force is arbitrary, it doesn't change the outcome. That might sound strange, but any change in the force has to be compensated for by applying it for a different length of time so you end up with the same change in momentum.Quote:Im not sure why your so concerned with time as the time is given in the acceleration of the mass.Have a free floating stationary block of 1kg. Push it with 10N for 1s. Then run round the other side and push it in the opposite direction with 10N for 1 hour. The block ends up stationary of course, because the two opposite forces balance, right?Quote:maybe that is where your insertion of 2 seconds will come in !!!As I said before, there's no point going into other details unless you understand what that factor of 2 is for. Without it, the machine will indeed fly. Why don't you try to understand it? Don't have to listen to me, go check google or ask someone else. Or just look at this: Answer to a physics problem. Edited by kallog (06/22/10 01:00 PM) Top
 #35103 - 06/22/10 02:08 PM Re: Orion, Mission to Alpha Centauri paul Megastar Registered: 03/21/06 Posts: 4136 ************** the second cycle ***********************the 100 kg mass is accelerated at 5 m/s/s with the 500 N force.for a distance of 152.4 meters.-----------------------------------------the mass...-----------------------------------------its initial velocity is 39.0385 m/sits final velocity is 52.193 m/sits average velocity is 57.930 m/sthe time it takes the mass to accelerate the 152.4 meters is 2.6309 secondsits braking force is 5219.3 N-----------------------------------------the pipe...-----------------------------------------mass = 500 kgforce is 500Ninitial velocity is 7.8077 m/sfinal velocity is 10.4386 m/saverage velocity is 11.586088965 m/sthe final pipe velocity is 10.4386 m/sthe pipe has now moved a distance of 60.961 metersthe braking force of the pipe is 5219.3 N**************** the third cycle ***********************the 100 kg mass is accelerated at 5 m/s/s with the 500 N force.for a distance of 152.4 meters.-----------------------------------------the mass...-----------------------------------------its initial velocity is 52.193 m/sits final velocity is 63.736 m/sits average velocity is 66.0178799 m/sthe time it takes the mass to accelerate the 152.4 meters is 2.3086 secondsits braking force is 6373.6 N-----------------------------------------the pipe...-----------------------------------------mass = 500 kgforce is 500Ninitial velocity is 10.4386 m/sfinal velocity is 12.7472 m/saverage velocity is 13.203 m/sthe final pipe velocity is 12.7472 m/sthe pipe has now moved a distance of 91.443 metersthe braking force of the pipe is 6373.6 Nwith each cycle the mass will be accelerated faster and fasterwhich in turn will accelerate the pipe faster and faster.using only 1 mass is stupid but it seems to allow for your understandingthat the pipe will move as I stated , using a constant acceleration of masses would be the ideal method to accomplish a smoother acceleration.WOW , just think kallog in a few more cycles the mass willrequire less than 2 seconds for acceleration , and your 4 second requirement for the mass to pass through the 2 turnarounds would make the concept , non working...must be nice to just pick a time requirement out of thin air to use in your favor in a discussion. _________________________ 3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science. Top
 #35104 - 06/22/10 08:11 PM Re: Orion, Mission to Alpha Centauri [Re: paul] paul Megastar Registered: 03/21/06 Posts: 4136 I found a flaw in my calculations , that gave incorrect numbers above.the flaw is now corrected and I am posting the corrections.************** the second cycle ***********************the 100 kg mass is accelerated at 5 m/s/s with the 500 N force.for a distance of 152.4 meters.-----------------------------------------the mass...-----------------------------------------its initial velocity is 39.0385 m/sits final velocity is 55.209 m/sits average velocity is 47.12375 m/sthe time it takes the mass to accelerate the 152.4 meters is 3.2341 secondsits braking force is 5520.9 N-----------------------------------------the pipe...-----------------------------------------mass = 500 kgforce is 500Ninitial velocity is 7.8077 m/sfinal velocity is 11.0418 m/saverage velocity is 9.42475 m/sthe final pipe velocity is 11.0418 m/sthe pipe has now moved a distance of 60.96067362 metersthe braking force of the pipe is 5520.9 N**************** the third cycle ***********************the 100 kg mass is accelerated at 5 m/s/s with the 500 N force.for a distance of 152.4 meters.-----------------------------------------the mass...-----------------------------------------its initial velocity is 55.209 m/sits final velocity is 67.617 m/sits average velocity is 61.413 m/sthe time it takes the mass to accelerate the 152.4 meters is 2.4816 secondsits braking force is 6761.7 N-----------------------------------------the pipe...-----------------------------------------mass = 500 kgforce is 500Ninitial velocity is 11.0418 m/sfinal velocity is 13.5234 m/saverage velocity is 12.2826 m/sthe final pipe velocity is 13.5234 m/sthe pipe has now moved a distance of 91.44117378 metersthe braking force of the pipe is 6761.7 Nwith each cycle the mass will be accelerated faster and fasterwhich in turn will accelerate the pipe faster and faster.using only 1 mass is stupid but it seems to allow for your understandingthat the pipe will move as I stated , using a constant acceleration of masses would be the ideal method to accomplish a smoother acceleration.WOW , just think kallog in a few more cycles the mass willrequire less than 2 seconds for acceleration , and your 4 second requirement for the mass to pass through the 2 turnarounds would make the concept , non working...must be nice to just pick a time requirement out of thin air to use in your favor in a discussion.using 20 sets of tubes with 1 mass in each in 1 year the pipe could travel a distance of 5.2 trillion miles.using 40 sets in 1 year the pipe could travel a distance of 10.43 trillion miles.hey thats over 330,000 miles /second.The speed of light is 186,000 miles per secondwhich can cut the 1 year travel time of 5.2 trillion miles in half to 6 months. _________________________ 3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science. Top
 #35105 - 06/22/10 09:52 PM Re: Orion, Mission to Alpha Centauri paul Megastar Registered: 03/21/06 Posts: 4136 that is the CHANGE IN MOMENTUM OF THE BALL kallog.the ball still presents the same force to the wall.the force that is its mass * velocity.or your used to using p=mvthe momentum that is its mass * velocityjust like the mass still presents the same force to the U turns.its the elastisity of the ball that allows it to bounceoff the wall.like compressing a spring.the ball is compressed like a spring because of its momentum. _________________________ 3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science. Top
 #35106 - 06/22/10 10:19 PM Re: Orion, Mission to Alpha Centauri [Re: paul] paul Megastar Registered: 03/21/06 Posts: 4136 I must admit that given this new turn of events , I would have to say that I think we could travel to other solar systems using current energy technologies , that is if we remain too stupid to use free energy sources. _________________________ 3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science. Top
 #35107 - 06/22/10 11:52 PM Re: Orion, Mission to Alpha Centauri [Re: paul] kallog Megastar Registered: 03/17/10 Posts: 1100 Quote:the 2 seconds that you are using is a complete falsity.How long do you think it'll take? Here's a hint. F=3900N, m=100kg, initial speed = 39m/s, F=ma. Any ideas?Or rather than wasting time, why don't we just change the arbitrary 3900N force that you chose. Make the turnaround force 100,000N and it'll take much less than 2s.Quote:because afterall that is what you are trying to do , you just cant do it because physics keeps getting in the way , spoiling your attempts.I've noticed that every single insult you fire at me is actually describing yourself, not me. Where are your equations? I mean the ones using physics, not just made up. F=mv is just made up. Top
 #35109 - 06/23/10 02:33 AM Re: Orion, Mission to Alpha Centauri paul Megastar Registered: 03/21/06 Posts: 4136 kallogQuote:How long do you think it'll take? Here's a hint. F=3900N, m=100kg, initial speed = 39m/s, F=ma. Any ideas?if the mass is traveling at a velocity of 39 m/s and the U turn is 39 meters long , it will take exactly 1 second.if the mass is traveling at a velocity of 39 m/s and the U turn is 19.5 meters long , it will take exactly 1/2 second.if the mass is traveling at a velocity of 39 m/s and the U turn is 9.75 meters long , it will take exactly 1/4 second.picture a car on a hill beside a U shaped valley , the car coast down the hill but the car begins to coast up the other hill.the other hill is the same size and shape of the first hill.if resistance and friction are zero , the car could coast up to the top of the other hill. but will the car need assistance from the hill to coastup to the other hill?if so and given that the hill itself will not move and provide a force that would assist the car up the hillhow then can the hill assist the car?the momentum of the car causes the car to go down the first hill and up the second hill.the car lost all of its momentum in doing so.just like the momentum of the mass causes the mass to go half way through the U turn and then through the other half of the U turn.except the mass has a veocity before it enters the U turn.now suppose the car was dropped from a height of 500 ft, the cars momentum would be enought to send the car down one hill and up the other hill , and all the way back up to the altitude it was first dropped from.Quote:F=mv is just made up.nope , its used in hydraulics all the time when describing a fluid pressure that acts against a piston.there is no time added because the time is itself addedvia a=f/mie.. apply a force of 10 lbagainst a 1 inch hydraulic piston and you get a forceof 100 lb from a opposing 10 sq inch piston.the F=mv is used to calculate the force that the pistonitself can place on the fluid because of its mass * velocity.a lighter piston = less forcea heavier piston = more forcea lighter piston less force required to move the piston itself.a heavier piston more force required to move the piston itself.some people work with pistons that weigh several thousand pounds.thus f=mv _________________________ 3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science. Top
 #35110 - 06/23/10 03:48 AM Re: Orion, Mission to Alpha Centauri [Re: paul] kallog Megastar Registered: 03/17/10 Posts: 1100 Originally Posted By: paulits final velocity is 52.193 m/sits braking force is 5219.3 NThat force is chosen arbitrarily. It need not be 5219.3N. And in fact it cannot be now that you demand <<2s turnaround.a=F/ma = 5219.3N / 100kga = 52.2 m/s^2At that acceleration/deceleration, how much time do you think it'll take to stop or turn around?You must specify a higher braking force. Top
 #35111 - 06/23/10 04:03 AM Re: Orion, Mission to Alpha Centauri [Re: paul] kallog Megastar Registered: 03/17/10 Posts: 1100 Originally Posted By: paulthat is the CHANGE IN MOMENTUM OF THE BALL BINGO!Quote:the force that is its mass * velocity.I don't care where you got this equation from or what other applications it's used in. IT IS AUTOMATICALLY WRONG. Why? Because the dimensions are inconsistent:F = 100kg * 40m/sF = 4000 kg m/sIs "kg m/s" a unit of force? Can you convert it to newtons?You can check with these google searches:"4000 kg m/s in N""4000 kg m/s^2 in N"Here's another reason it can't be right:You claim:F=maF=mv andp=mvTherefore:F=pma=mva=vAcceleration is always equal to velocity??Quote:or your used to using p=mvthe momentum that is its mass * velocityAt least we agree on something. Top
 #35112 - 06/23/10 04:06 AM Re: Orion, Mission to Alpha Centauri [Re: paul] kallog Megastar Registered: 03/17/10 Posts: 1100 Originally Posted By: paulremain too stupid to use free energy sources. No, magic carpets are much better than free energy. Sadly whenever somebody flies a magic carpet, the CIA shoots them. That's why we find bodies dropping out of the sky from time to time. Top
 #35115 - 06/23/10 11:34 AM Re: Orion, Mission to Alpha Centauri paul Megastar Registered: 03/21/06 Posts: 4136 Quote:a=F/ma = 5219.3N / 100kga = 52.2 m/s^2At that acceleration/deceleration, how much time do you think it'll take to stop or turn around?if the turn around is 52 meters long it will take exactly 1 second to turn around because its velocity is 52m/s.if the turnaround is shorter it will take less time.if you apply a force of 5219.3N for 1 second you can stop it in 1 second and 1 meter distance.applying less force will not stop it as fast and will also require more stopping distance.applying more force will stop it faster and in less stopping distance. _________________________ 3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science. Top
 #35116 - 06/23/10 12:01 PM Re: Orion, Mission to Alpha Centauri [Re: paul] kallog Megastar Registered: 03/17/10 Posts: 1100 Originally Posted By: paulapplying less force will not stop it as fast and will also require more stopping distance.applying more force will stop it faster and in less stopping distance. Yea. So if we need <<2s turnaround time we have to use a higher force. 5219N takes 2s and 104m to turn the mass around.100,000N?a=F/ma=-100,000N / 100kga=-1000m/s^2time = (change in v) /atime to stop = -52.2m/s / (-1000m/s^2)time to stop = 0.0522sdistance to stop = -1/2 a t^2distance to stop = 1.36mEquations from equations of motion Top
 #35117 - 06/23/10 12:06 PM Re: Orion, Mission to Alpha Centauri paul Megastar Registered: 03/21/06 Posts: 4136 Quote: Yea. So if we need <<2s turnaround time we have to use a higher force. 5219N takes 2s and 104m to turn the mass around. Kallog , its not STOPPING !!!!why cant you GRASP that ?no force is REQUIRED to TURN IT AROUND _________________________ 3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science. Top
 #35118 - 06/23/10 01:23 PM Re: Orion, Mission to Alpha Centauri [Re: paul] kallog Megastar Registered: 03/17/10 Posts: 1100 Suppose a car's coasting towards you at 100km/hr.You can turn it around using no force. So you can reach out your hand, grab the wing mirror, and the car will spin round and head off in the opposite direction as you let go at the right time.F=ma. Please look up Wikipedia or a high-school general science textbook instead of saying made up things.Originally Posted By: paulQuote:To a physicist, 'acceleration' includes a change in speed or direction. Look up wikipedia to get a more thorough picture. This is the same acceleration in F=ma so it's crucial that we use a consistent definition.I have a clear understanding of that , and physicist also use decelerate to describe using a force to decelerate a object.picking at straws are we? Edited by kallog (06/23/10 01:27 PM) Top
 #35119 - 06/23/10 01:50 PM Re: Orion, Mission to Alpha Centauri [Re: paul] kallog Megastar Registered: 03/17/10 Posts: 1100 I think it's starting to come together now.The recurring problems you have would be consistent with treating velocity and momentum as scalars. Maybe you don't realize they're vectors? F=ma and p=mv are actually a vector equations. They can give wrong results if you only put the magnitudes of the quantities into them.Can an object accelerate if its speed remains constant?If an object reverses direction, must its momentum change?If an object reverses direction, must its velocity change?If an object reverses direction, must its speed change?Is it possible to apply an unbalanced force to a moving mass without changing its speed? Top
 #35120 - 06/23/10 02:07 PM Re: Orion, Mission to Alpha Centauri paul Megastar Registered: 03/21/06 Posts: 4136 Originally Posted By: paulI have a clear understanding of that , and physicist also use decelerate to describe using a force to decelerate a object.which object is being decelerated then kallog?just tell me which object you think is being decelerated and what causes it to decelerate.ie..where does the force come from that decelerates the object?at what velocity does the object have the entire time it is decelerating.what is the objects final velocity when it has finished decelerating?if you are speaking about the mass as the object that is being decelerated.1) how can a object declerate without changing its velocity.2) there is no 2the change in momentum you are talking about is nothing buta change in the direction of the object.that change in direction does not have anything to do withthe momentum of the pipe.the force that the object presents to the pipe as it presses against the pipe while turning around is the only force that the object can possibly apply to the pipe while turning around.and it will present a force that is exactly its mass * its velocity.How Force is related to MomentumMomentum measures the 'motion content' of an object, and is based on the product of an object's mass and velocity. Momentum doubles, for example, when velocity doubles. Similarly, if two objects are moving with the same velocity, one with twice the mass of the other also has twice the momentum. Force, on the other hand, is the push or pull that is applied to an object to CHANGE its momentum. Newton's second law of motion defines force as the product of mass times ACCELERATION (vs. velocity). Since acceleration is the change in velocity divided by time, you can connect the two concepts with the following relationship: force = mass x (velocity / time) = (mass x velocity) / time = momentum / time Multiplying both sides of this equation by time: force x time = momentum _________________________ 3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science. Top
 #35121 - 06/23/10 02:41 PM Re: Orion, Mission to Alpha Centauri [Re: paul] kallog Megastar Registered: 03/17/10 Posts: 1100 Originally Posted By: pauljust tell me which object you think is being decelerated and what causes it to decelerate.I wouldn't use the term "decelerate" here because it's a bit vague. I would use "accelerate". The mass going through the u-bend is accelerating all the way through.Quote:at what velocity does the object have the entire time it is decelerating.While it's turning around its velocity is continuously changing from, say 39m/s to the left, through 39m/s upward, till finally reaching 39m/s to the right. Its speed remains the same throughout.Quote:1) how can a object declerate without changing its velocity.It can't. The velocity must change. Therefore, by definition, it is accelerating.Quote:the change in momentum you are talking about is nothing buta change in the direction of the object.Yes a change in direction. Which is a change in momentum. But not a change in the _magnitude_ of momentum.Quote:the force that the object presents to the pipe as it presses against the pipe while turning around is the only force that the object can possibly apply to the pipe while turning around.Of course. That's the only force I've been talking about all the time, as well as its equal and opposite reaction. What force were you thinking of?Most of what I just said will appear self-contradictory if you consider 'velocity' and 'speed' to be the same thing. Top
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